The present invention relates to a device and method for measuring an area, particularly adapted to measure areas with complicated geometries.
There are numerous situations in which the area inside a boundary must be determined. For instance, the area of a driveway must be determined to estimate the amount of concrete required for a new pavement. Likewise, the area of a room must be determined before it may be carpeted.
Methods and devices exist for measuring an area in such situations. For example, one such device is intended to measure distances and includes a wheel attached to a support. The wheel may be rolled from one point to another point to determine the distance between the points. A counter associated with the wheel tracks the number of revolutions. This number, multiplied by the circumference of the wheel, yields the distance traveled. This device may be used to measure the area inside a rectangle. First, the device is used to determine the length and width of the rectangle. These two lengths are then multiplied to determine the area. This process is inconvenient, however, in that it includes multiple steps and requires the user of the device to calculate the area manually. Furthermore, to calculate the area inside shapes more complicated than a rectangle, the measurements and calculations involved quickly become unwieldy.
Another device exists that can automatically measure the area of a rectangular room. When placed in the corner of the room, the device uses reflected laser beams to determine the distance to each of the two opposing walls. The device then automatically multiplies these two distances to calculate the area of the room. This device is limited, however, in that the area to be measured must be rectangular and must be bounded on at least two sides by walls.
Another conceivable approach to measuring an area is to use a global positioning system (GPS) to plot the boundary of the area. Once the boundary is plotted, an algorithm may be used to calculate the area inside the boundary. However, current commercially-available GPS transceivers are only accurate to within approximately one meter. This margin of error applies to each boundary point plotted. The total margin of error would be multiplied when the boundary points are used to calculate the area inside the boundary. Accordingly, a conventional GPS-based system is acceptable only for measuring very large areas for which the margin of error produced by the one-meter GPS system resolution is not significant.
An alternative to conventional GPS is differential GPS. Differential GPS uses fixed ground stations to determine location more precisely, thereby achieving a reduced margin of error compared to that of conventional GPS. However, differential GPS is prohibitively expensive for use in many area-measurement projects.
There is therefore a need for an area measurement device that provides for convenient measurement of the area within a boundary. There is a further need for an area measurement device that is capable of conveniently measuring the area inside irregularly shaped boundaries. There is also a need for an area measurement device that is capable of conveniently measuring an area that is not bounded by walls or other structures.
According to one aspect of the present invention, the foregoing needs are addressed by a system for measuring the area inside a boundary. The system includes a support that may be moved around the boundary. A direction indicator is provided to determine the directional orientation of the support. The direction indicator is configured to create direction data as the support is moved around the boundary. A distance indicator is also provided. The distance indicator determines the distance traveled by the support and creates distance data as the support is moved around the boundary. A microprocessor is programmed to receive the direction and distance data and to use this data to calculate the area inside the boundary.
According to another aspect of the present invention, a system for measuring the area inside a closed boundary includes two wheels. The wheels are mounted to a support and may be rolled around the boundary. Distance indicators determine the distance traveled by each wheel and create distance data for each wheel as the support is moved around the boundary. A microprocessor is programmed to receive the distance data for each wheel from the distance indicators. The microprocessor compares the distance data for the two wheels to determine the distance traveled by the support and to create support distance data. The microprocessor also compares the distance data for the two wheels to determine the directional orientation of the support as it is moved around the boundary and to create direction data. The microprocessor is programmed to use the support distance data and the direction data to calculate the area inside the boundary.
According to a further aspect of the present invention, a system for measuring the area inside a closed boundary includes a rotatable ball that may be rolled around the boundary. As the ball is rolled around the boundary, X-Y position indicators convert the rotation of the ball into position data. A microprocessor is programmed to receive the position data and to calculate the area inside the boundary using this data.
According to a still further aspect of the present invention, a method may be used to measure the area inside a boundary. A support is moved around the boundary. The directional orientation of the support is determined at a number of positions along the boundary. The distance traveled by the support is also determined at a number of positions along the boundary. Direction data and distance data are created for each of the positions. The area inside the boundary is then calculated based upon this data.
Advantages of the present invention will become readily apparent to those skilled in the art from the following description of the preferred embodiments of the invention that have been shown and described by way of illustration. As will be realized, the invention is capable of other and different embodiments, and its details are capable of modification in various respects. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.